Nightbringer | The Arthurian Online Encyclopedia

Three Unfortunate Assassinations of the Island of Britain

Heidyn, son of Enygan, who slew Aneirin of Flowing-Verse, Prince of Poets; Llawgad Trwm Bargod Eidyn (‘Heavy Battle-Hand of the Border of Eidyn’) who slew Afaon, son of Taliesin; and llofan Law Ddifo (‘Ll. Severing Hand’) who slew Urien, son of Cynfarch.

Red Book of Hergest | C. 1425
Text of the Mabinogion and Other Welsh Tales | John Rhys, 1887